Alert archive / Arizona / Flash Flood Warnings in 2002

Flash Flood Warning 12, NWS Flagstaff, AZ

July 24, 2002Coconino County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 24, 2002, 4:30 PM MST for Coconino County, Arizona. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 24, 2002, 4:30 PM MST (23:30 UTC)
Expired: Jul 24, 2002, 6:30 PM MST
In force: 2 hr
Issued by: NWS Flagstaff, AZ
Area: Counties, with a storm outline in the text

County Coconino County, AZ

The radar

The Cedar City radar (KICX), 150 km from the middle of the area, began a volume at 23:31 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 11.5 hours before the alert went out and 138 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 176 J/kg
Mixed-layer CIN: -72 J/kg
Mixed-layer LCL: 1290 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 12 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS55 KFGZ 242330
FFWFGZ
AZC005-250130-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
426 PM MST WED JUL 24 2002

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL COCONINO COUNTY IN NORTH CENTRAL ARIZONA
  THIS INCLUDES THE VILLAGE OF SUPAI

* UNTIL 630 PM MST

* AT 426 PM MST...BOTH PUBLIC AND RADAR REPORTS INDICATED VERY HEAVY
  RAIN OVER SUPAI. THIS AREA OF RAIN WAS NEARLY STATIONARY.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO
TRIGGER ROCK AND MUDSLIDES IN STEEP TERRAIN.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT. IT IS
IMPORTANT TO KNOW WHERE YOU ARE RELATIVE TO STREAMS...RIVERS...OR
CREEKS WHICH CAN BECOME KILLERS IN HEAVY RAINS. CAMPERS SHOULD AVOID
CAMPING ALONG STREAMS OR CREEKS DURING THREATENING RAINS.

IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY. 
DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN 
DEPTH.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE.

LAT...LON 3625 11279 3615 11264 3625 11253 3634 11264

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Flagstaff, AZ wrote its last area forecast discussion before this flash flood warning went out at Jul 24, 2:30 PM MST, 2 hours earlier.

Area forecast discussion, Jul 24, 2:30 PM MST, 2 hours before

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST WED JUL 24 2002

.SYNOPSIS...THE DAILY SHOWERS AND THUNDERSTORMS WILL CONTINUE
THROUGH THE END OF THE WEEK. A DOWN TREND IN THE SHOWER AND
THUNDERSTORM ACTIVITY IS EXPECTED OVER THE WEEKEND AS WESTERLY
FLOW ALOFT BRINGS DRIER AIR INTO NORTHERN ARIZONA. TEMPERATURES
WILL REMAIN SEASONAL.

.DISCUSSION...DEEP LAYER MID-LEVEL ANTICYCLONIC CIRCULATION WAS
LOCATED OVER THE FOUR-CORNERS REGION THIS AFTERNOON. ANTICYCLONE
WILL SHIFT EASTWARD OVERNIGHT AS A MID-LEVEL TROUGH MOVES OVER THE
GREAT BASIN. THE TROUGH WILL REMAIN ESSENTIALLY STATIONARY OVER THE
GREAT BASIN FROM THURSDAY INTO SATURDAY WITH DEEP BUT WEAK SOUTHWEST
FLOW DEVELOPING. FOR TONIGHT...THINK WITH DEVELOPING TROUGH AND DEEP
MOISTURE STORMS WILL BE POSSIBLE ALL NIGHT. THEY WILL BE MOST
NUMEROUS DURING THE EVENING HOURS. ON THURSDAY...FLOW SHIFTS TO
SOUTHWEST THROUGH A DEEP LAYER. WITH DEEP MOISTURE OVER WESTERN
ARIZONA THINK THIS WILL ADVECT ACROSS THE AREA ON THURSDAY.
SOUTHWEST TO WEST FLOW WILL FAVOR THE MOST NUMEROUS SHOWERS FROM THE
MOGOLLON RIM NORTHWARD. ACTIVITY WILL LIKELY INCREASE OVER THE
NORTHEAST PORTION OF THE STATE ON THURSDAY. ON FRIDAY...THINK
MOISTURE WILL STILL BE SLOW TO MOVE BUT WILL GO WITH ONLY A SLIGHT
CHANCE OVER THE FAR WESTERN COUNTY WARNING AREA (CWA) AS A COOLER
AIR MASS MOVES IN FROM THE PACIFIC AND STABILIZES THINGS. THINK
THERE WILL STILL BE A FAIR AMOUNT OF THUNDERSTORMS ALONG THE
MOGOLLON RIM...WHITE MOUNTAINS NORTHWARD. BY SATURDAY DRYING
CONTINUES WITH ONLY ISOLATED TO SCATTERED STORMS WITH PACIFIC AIR
MASS MOVING OVER MORE OF THE CWA.

IN THE EXTENDED...THE FLOW GETS VERY COMPLICATED. ARIZONA WILL BE
UNDER A WEAK TROUGH/FLOW BETWEEN THE EASTERN PACIFIC SUBTROPICAL
RIDGE TO THE NORTHWEST AND THE ATLANTIC SUBTROPICAL RIDGE TO THE
SOUTHEAST. LOOKS LIKE THE TREND WILL BE TOWARD SOME DRYING AS FLOW
TRENDS FROM THE WEST. WESTERLY FLOW USUALLY BRINGS IN DRIER AIR AT
ALL LEVELS WITH SOME COOLING IN THE LOWEST LEVELS WHICH PUTS A
DAMPER ON THUNDERSTORM ACTIVITY. HOWEVER...WITH THE UNCERTAINTIES
ASSOCIATED WITH THE COMPLEX INTERACTION OF SYSTEMS NOT CERTAIN IT
WILL COMPLETELY STABILIZE. AS A RESULT...WILL CONTINUE WITH A CHANCE
OF SHOWERS AND THUNDERSTORMS THROUGH THE EXTENDED.

MCCOLLUM

.FGZ...NONE

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES LO/HI           PROBABILITY OF PRECIP
                 TON THU   FRI     SAT        TON THU   FRI     SAT
FLAGSTAFF        053/077 054/078 052/080      030 070 030 040 020 030
WINSLOW          063/088 065/088 063/090      030 060 030 040 020 030
PRESCOTT         062/086 063/087 061/089      030 050 020 020 020 020
PAGE             072/092 072/094 070/096      020 060 030 020 020 020
WINDOW ROCK      054/080 055/079 052/081      020 070 050 050 040 040
CANYON DE CHELLY 060/086 061/085 058/087      020 060 040 040 030 030
COTTONWOOD       070/097 071/098 069/100      020 040 020 020 020 020
GRAND CANYON     052/079 053/080 051/082      020 060 020 030 020 020
GREER            049/073 050/074 048/076      040 080 050 060 040 050
HEBER            054/082 055/083 053/085      040 060 050 050 030 040
JACOB LAKE       053/075 054/076 052/078      020 060 020 030 020 020
NAVAJO N.M.      058/080 059/079 056/081      020 060 040 040 030 030
PAYSON           063/091 064/092 062/094      030 020 020 020 020 020
SEDONA           068/095 069/096 067/098      020 040 020 020 020 020
SELIGMAN         055/089 056/090 054/092      020 040 010 010 010 010
SHOW LOW         061/083 062/084 060/086      030 060 040 040 030 030
ST. JOHNS        058/082 060/082 058/084      040 070 040 050 030 040
WUPATKI N.M.     066/090 068/090 066/092      030 060 030 050 020 030

The office that day

Everything else NWS Flagstaff, AZ issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 24, 4:26 PM MST	Flash Flood Warning	FGZ	Coconino	64 min

Nearby

Flash Flood Warnings in Arizona, 2002 Every flash flood warning in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.